One dimensional calculation of the

One dimensional calculation of the first stage of the centrifugalturbine are carried out based on the given design parameters. Theinitial enthalpy DH1t, the reaction degree U1 and the speed ratio x1a(xa ¼ u=ca) of the first stage and the density at the first rotor outletr1;2 are previously estimated. The maximum wheel efficiency isused as the optimization objective and the difference between theactual density and estimated density r01;2 r1;2h1  106 at therotor outlet is used as restrictive condition. Screening method isused for the optimization. The above equations are solved iteratively.Once the diameters of both stator and rotor D, the height ofthe blade H, and the inlet absolute flowangle a1 have been selected,the isentropic efficiency can be calculated.The above procedures are also adopted to design the second andother following stages of the centrifugal turbine. A constant heightblade is used as a restriction, and geometric parameters includingrotor diameter ratio b, the flow angles a1 and the reaction degree ofeach stage are optimized to ensure the maximum efficiency of thecentrifugal turbine. In the final step, the blade numbers are determinedmainly based on empirical factors such as relative pitch andexpelling coefficient which are determined from both previousexperience and the published data provided for axial flow turbines.

結果 (繁體中文) 1:

將其轉化入一個無量綱的等熵效率
通過使用等式量。（9）和等式。（10）可以表示為
等式 （12）。

結果 (繁體中文) 2:

被轉化為無維的等向效率
使用 Eq.（9） 和 Eq.（10） 的數量可以表示為
Eq. （12）。

結果 (繁體中文) 3:

轉化為無量綱的等熵效率
用式（9）和式（10）表示的量可以表示為
式（12）。